Drilling-machine



Patented Apr. l8, I899.

no. 623,l40.

H. H. CUMMINGS.

DRILLING MACHINE.

, (Application filed Jan. 10, 1898.)

3 Sheets-Sheet l.

040 Model.)

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N J Patented Apr; l8, I899.

H. H. CUMMINGS, DRILLING MACHINE.

(Application filed Jan. 10, 1898.)

3 Sheets-Sh'eet 2.

(No Model.)

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K lgwwsaea jvvaroeon dam/10C flwfl 6202714 15 5 ihvrrnn STATES PATENT()rr cn.

HENRY H. CUMMINGS, OF MALDEN, MASSACHUSETTS DRILLING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 623,140, dated April18, 1899.

Application filed January 10' 1898- Serial No. 666,185. (No model.)

To It 111700771 it may concern: Be it known that 1, HENRY H. CUMMINGS,of Malden, in the county of Middlesex and State of Massachusetts, haveinvented an Improvement in Drilling-Machines, of which the followingdescription, in connection with the accompanying drawings, is aspecification, like letters and numerals on the drawings representinglike parts.

This invention relates more particularly to upright drills, and has forits object the prod uction of various novel features of construction insuch apparatus whereby the operation thereof is improved and made morereadily controllable by the operator.

I have provided convenient speed-changing mechanism in connection withthe rotatable tool-holding spindle, and in connection with suchmechanism I employ a suitable movable toolrack so arranged that byproper movement thereof the speed of the tool-spindle will beautomatically regulated in accordance with the diameter of the drill orother tool to be used.

Various other features of my invention will be hereinafter fullydescribed in the specification and particularly pointed out in theclaims.

Figure 1, in side elevation, represents an upright drill embodying mypresent invention, the standard being partially broken out. Fig. 2 is avertical sectional view of a portion of the platen-carrier on the linea: m, Fig. 1, looking to the left. Fig. 2 is a horizontal sectional viewthereof on the line 00 w thereof, Fig. Fig. 3 is an enlarged top or planview of the head of the apparatus shown in Fig. 1 and partially brokenout. Fig. 4 is a vertical sectionalview of the head,taken on theirregular line Ma, Fig. 3. Fig. 5 is a detail in side elevation andpartly broken out of the means for controlling the power-transmittingmechanism of the tool-spindle. Fig. 6 is a vertical transverse sectionof the head on the line a in", Fig. 4, looking toward the right. Fig. 7is an enlarged side elevation, partly broken out, of the traveler andthe feed mechanism carried thereby. Fig. 7 is a detail view of thecontrolling device for the tool-feed mechanism. Fig. 8 is a horizontalsectional view of y y, some of the gears being in elevation; and Fig. 9is a partial front view of the mechanism shown in Fig. 5.

The working parts of the apparatus are sup ported on an uprightcylindrical and preferably hollow column or standard A, having alaterally-extended base A the standard having on its exterior a verticalguide A for the traveler, to be described, and a longitudinal recess Ain the standard receives a threaded shaft or rod to. As shown in Fig. a,the upper end or head A of the standard has a bearing a for the hub a ofthe bevel-geared, secured to the rod to and shouldered at a the gear androd being rot-atabl y supported in the bearing by the shoulder. Ahand-lever a, pivoted on the head at a is bifurcated at its inner end toembrace loosely the rod or shaft a beneath the hub a to raise or lowersaid shaft slightly, for a purpose to be described.

The platen or work-support B, of usual construction, is mounted on aplaten-carrier B the latter being provided with asplit hub B to embracethe standard A, the parts of the carrier separated by the slit 2, Fig.2, being connected by suitable clamp-bolts Z), the eyes I) of which areengaged by eccentric portions 1) of a stud mounted in ears 3 of thecarrier and actuated by a lever-arm b The interior of the hub B? isannularly recessed, as at N, Figs. 2 and 2, to receive therein and forma guide for the ends of a block 19 having a threaded ear 19 into whichthe threaded shaft centers. Byrotation of the latter the platencarrier Bis raised or lowered, the carrier at such time being unclamped, rotationbeing transmitted to the shaft Ct through the gear a It will be seen inFigs. 1 and 4 that normally the shaft ais out of gear with its operatingmechanism, and so long as the platencarrier B is clamped the shaftcannot be moved longitudinally by the lever a to bring it into mesh tobe rotated, thus effectually preventing accidents due to oversight orcarelessness.

The head A ofthe standard is bent over to provide an overhanging arm AFigs. 1, 3, and 4, having a vertical bearing a, preferably bushed, as ata Fig. 4, to receive the sleevelike hub 0 of a large bevel-gear c, acollar a the mechanism shown in Fig. 7 on the line 1 fast on the upperend of the hub resting on the overturned end of the bushing andretaining the gear in place. Within the bevelgear is a smallerbevel-gear 0, (see Fig. 4,) secured thereto, as by screws 6, the facesof bot-h gears being upturned, the gear 0 being formed on an annularflange 0 provided on its exterior with preferably undercut grooves 7 7,for a purpose to be referred to.

The drill or tool spindle D is. extended through the hub e and islongitudinally grooved at 8 to receive a suitable spline on the hub, asis common in drills, whereby the spindle is rotated with the gears c andc and also longitudinally movable relatively thereto to feed the tool tothe work. A sleeve (Z is secured to the lower end of the spindle, havinga longitudinal rack-bar on its inner side to mesh with the teeth of thehub (2 forming part of an internal gear 61 and external worm-gear (Zsaid hub being rotatably mounted on the horizontal shaft (Z (see Fig. 8)of a hand-wheel D This shaft has a hearing at one end in the side of thecasting E, forming the traveler, the other side of the traveler having aboss d to provide a hearing for the hub (Z a vertical bearing (1embracing the spindle-sleeve (Z and being cut away at (Z to receive therack-bar d.

When the worm-gear d is rotated by a worm d on an upright shaft (1 thespindle D is moved longitudinallyto feed the tool T, Fig. 1, held in asuitable chuck D on the lower end of the spindle.

It is sometimes desirable to control the feed of the tool by hand, andfor this purpose I have secured to the rear end of the shaft d a piniond in mesh with the gear (Z on one end of a short shaft (Z the other endof the short shaft having a pinion c 15 fast thereon.

This short shaft, as shown in Fig. 8, is extended through a sleeve-likebearing (1, fast on a controller-plate (PT, the sleeve being extendedthrough one side of the traveler E and forming the fulcrum for thecontroller-plate, a bearingd formed on the inner face of the other sideof the traveler, receiving in it the free end of the shaft d. ,Anintermediate gear d is pivoted on the controller-plate and in mesh withthe pinion (Z When the controller-plate is swung into its oppositeextreme position from that shown in Fig. 7, the intermediate gear (Z isbrought into mesh with the internal circular gear (1 and by rotating thehand-wheelD a slow powerful feed will be effected through the pinion (Zgear (Z pinion (Z and intermediate (1 to the hubgear (2 and thence tothe feed-rack b. If it is desired to run the tool-spindle up or downrapidly, the controller-plate (Z is moved into mid-position, as shown inFig. 1, which disengages the Worm (Z and worm-gear (1 while it does notthrow the intermediate d into engagement with the gear d At the sametime a pin (Z on the hand-wheel D is pushed into one of several holes (Z(see dotted lines, Fig. 7) in the combined worm-wheel and internal gear,so that the latter will be rotated with the hand-wheel, thustransmitting move ment through the hub-gear d directly to the rack b.

The lower end of the shaft (Z is preferably made spherical, as at 20,Fig. '7, to fit into a correspondingly-shaped recess in a bearingplate21, fulcrumed at 22 on the traveler, said bearing-plate having fastthereon an arm 23, the end of which fits loosely into a notch 24: in thecarrier-plate, thus making therewith a species of toggle-joint.

The controller-plate is provided at its outer end with a handle 6 theinner extended end of which forms a latch (Z to enter one or morerecesses, as (Z in a locking-plate (Z on the side of the traveler, thelatch being normally pressed toward the locking-plate by a suit ablespring .9. WVhen the controller-plate is to be moved by hand, theoperator grasps the handle 61 and turns it, to withdraw the latch (Zagainst the pressure of the spring, thereby swing the bearing-plate 21to the right to thus move the worm d from engagement with the worm-gear(1 The inner face of the latch 61 maybe beveled in order to be engagedby a trip, shown as a finger25, Fig. 1, carried by the sleeve (1, andwhen the spindle is fed down to the proper point the finger 25 will passbeneath the latch and lift itfrom the holding-notch, the weight of thecontroller-plate moving it into position to disengage the worm andworm-gear.

Referring to Fig. 4, the worm-shaft (Z is extended up through a support27, secured to or forming part of an upturned hub-like bearing (Zsocketed at its upper end at (Z to receive the ball-like head (Z of asleeve (Z and loosely surrounding the shaft (1 the lower beveled end ofthe sleeve resting upon a cam-collar d provided with a suitable handle(1 the cam-collar being sustained by the support 27. Thisball-and-socket hearing at the upper end of the worm-shaft (l permitsthe slight lateral movement thereof necessary to disengage the worm andworm-wheel without interfering with the rotative or longitudinalmovement of the shaft, the latter being necessary when the traveler ismoved up or down on the'standard A, a counterbalancing-weight WV beingattached by a flexibleconnect-ion 4 (see dotted lines, Fig. 1) to thetraveler, the connection or connections passing over one or moreguide-sheaves 5.

A collar a on the sleeve-hub e is shaped to form a pulley a connected bya suitable belt 64 with the driving member a of a speed controllingmechanism, the driven member (0 of which is represented as a heavycasting splined to the shaft cZ -and located above the spherical head (ZThe driving and driven members are provided on their inner faces eachwith an annular concavity, as clearly shown in Fig. 4, and one or morefrietion-wheels c0 are interposed between said members and within theirgrooves mounted to rotate in the forked ends of suitable shafts a,having their hearings in a casting a, rigidly secured to the bearing (1.The two shafts are connected by intermeshing segment-gears a acted uponby a spring-controlled friction-pad a while one of the shafts a isprovided with a hand-le ver (L21.

The speed-changing mechanism shown is substantially such as forms thesubject-matter of United States Patent No. 529,713, granted to meNovember 27, 1894, and to which reference may behad, rotation of theshafts a" moving the peripheries of the friction-wheels a toward or fromthe center of rotation of the shaft (Z thus varying the speed impartedby the driving member a to the driven member a. The weight of thislatter.member' provides sufficient pressure to normally maintain thedevice operative, and when it is desired to throw the speedcontrollingmechanism out of operation the cam-ring (Z is moved to lift the sleeved, and thereby the driven member a, raising the latter from contact withthe friction-wheels a By the mechanism herein shown the feed of the toolis absolutely under the control of the operator, and by the movement ofthe lever a the speed of the feed can be controlled with great delicacy.

The traveler E is split at 30, as shownin Fig. 8, and provided withclamping-ears 31 to embrace the guide A, a'clamping device E, of usualconstruction in such apparatus, being provided to clamp the traveler inadjusted position.

The head of the standard, at its rear end, is provided with anoverhanging arm A to which is secured, as by screws 34, the upper end ofa substantially -shaped casting G, the lower laterally-extended ends ofthe latter having upright hubs or bearing-bosses g (most clearly shownin Fig. 6) to receive the lower ends of upright rotatable standards 9',bifurcated at their upper ends to receive and support rotatable friction-wheels g The said standards are provided with gears g in mesh with thetoothed outer edges g of segment-gears g, (see dotted lines, Fig. 3,)the latter meshing with each other and being fulcruined at g on thelower end of the casting G, so that rotative movementof either standardg will impart a like rotative movement, but in the opposite direction,to the other standard. The casting G is longitudinally bored at G Fig.4, to receive therethrough a sleeve 72, secured in the casting byaclampscrew 40, Fig. 4, and forming a bearing for the rear end of themain shaft H, said shaft having another bearing at h in the part of thehead A as shown in said Fig. 4. The main shaft has secured thereto thehub m of a friction-pulley M,.the said pulley having in its faceconcaved annular grooves adapted to be entered by the shiftable frictiondisks or wheels g described, the latter having, preferably, non-metallicperipheries. The sleeve h receives upon it the hub a of a secondfriction member N, provided with an annular flange N to form abelt-pulley and adapted to be driven by a belt from any suitable sourceof power and to be continuously rotated, the said member N having in itsinner face an annular concavity to be entered by the disks or wheels gThe outer end of the pulley N has a beveled annular face a, adapted tocooperate at times with a similarly-beveled face of a clutch member N,rigidly secured to the main shaft by set-screw 43, so that the clutchmember N and the friction member M will move simultaneously when theshaft H is moved longitudinally.

Referring to Fig. 4, it will be noted that the sleeve h is laterallyflanged at 7L2 at its outer end, and between the flange and the end ofthe hub n may be interposed washers to, preventing movement of thefriction member N longitudinally of the shaft to the right, viewing saidfigure.

The main shaft has thereon a beveled gear W, the hub of which isannularly grooved at h to be partially embraced by the bearing 72.,which is substantially semicircular in form, a key it on the shaftenteringa suitable longitudinal slot in the hub'of the gear, whereby thelatter will be rotated with the shaft, but permitting the latter to bemoved longitudinally therein. The beveled gear h is adjacent the likegear a on the upper end of the shaft a, and when the latter is raised bymeans of the hand-lever a the gears a and 71 are brought into mesh, sothat rotation of the main shaft will act through the vertical shaft toto raise or lower the platen-carrier B A bevel-gear h is provided with asleevelike hub 71.", through which the front end of the main shaft isextended, said hub being connected to the shaft to rotate therewith bythe key 7r", and a split collarh surrounds the hub loosely and isretained thereon by the upturned part of the flanged end of the hub hsaid collar being supported in a bearing h on the head. the gear 7Llongitudinally on the main shaft it is thrown into or out of mesh-withthe gear 0, which is fast on the hub e and a second bevel-gear h is alsomounted on the main shaft keyed thereto and longitudinally movablethcreon, the hub of the gear having an annular groove h Referring toFigs. 1, 4, and 5, a stud 70 projects from the side of the overhangingarm A and has mounted thereon the hub W of a hand-lever it, said hubnext the side of the arm having secured to it aplate 70 provided with acam-slot k to receive a roller or other stud k on the collar 77. theside of the arm A being slotted at to permit movement of the stud 70 asbest shown in Fig. 5. A yoke 70" enters the groove 71 of the hub or gearh and has pivoted thereto a link 70, piv- (See Fig. 4.) By moving Ix. xit otally connected at its other end to a wristpin on the outer side ofthe plate H, the pivot of the link passing through a slot 200 in thehead. (See Fig. 5, dotted lines.) If the handle 70 is swung up to turnthe hub and plate in the direction of the arrow 48, Fig. 5, the cam-slotk will act on the stud 7.5 to draw the gear h to the right, viewing Fig.l, and through the wrist-pin 70 and link 70 will draw the gear 70 to theleft. The effect of this is to disengage gears 70 and c and bring thegears 71 and 0 into engagement, and it will be obvious from the size ofthe gears c and c that the former will rotate the tool-spindle D slowlyand with'more power, While the gear 0 will rotate it at a higher speed,but not so powerfully. This provision for change of power on thetool-spindle is very convenient and increases the range of the machinein a very simple and effective manner.

An annularly-grooved collar 0, fast on the main shaft H, is embraced bythe forked end of an arm 0, pivoted at 0 on the inner end of aspring-controlled plunger 0 mounted in a bearing on the upturned portionA of the head, said arm 0 carrying near its lower end two parallel links0 pivoted on the arm at 0 and provided, preferably, withantifriction-rolls 44. A stud o rigidly secured in the part A of thehead,is extended through longitudinal slots 0 in the links and providesa fulcrum for a cam 0 interposed between the two rolls 44 and connectedabove its fulcrum by a rod 0 to a rocker-arm 0 keyed on a shipper-shaft0 mounted in the bearing 0 on the overhanging arm A and is provided witha shipper-lever 0 the shaft 0 sliding vertically through the rocker-arm.

It will be seen from the foregoing description that movement of theshipper-lever o to rock the shipper-shaft will act to swing the cam o inone direction or theother on its fulcrum to act upon one of the rolls44:,andthereby swing the forked arm 0 to the right or left, Fig. 4, tomove the main shaft longitudinally, the spring 3 on the plunger 0 takingup shock and preventing binding of parts, it being remembered that thepulley N and friction member N are continuously rotated. If the mainshaft is moved to the left, Fig. 4, the friction member N will bebrought into engagement with the cooperating face n of the pulley N ,sothat the shaft will be rotated in the same direction as and with thespeed of the pulley N the longitudinal movement of the shaft referred tomoving the friction member M to the left and removing the pressure fromthe intervening friction disks or wheels g On the other hand, if theshaft is moved into the position shown in Fig. 4

then the rotary movement of the friction member N will be transmitted tothe shaft through the friction member M by the friction-disks g and themember M and shaft will be rotated in a direction opposite to therotation of the member N and at a speed relative to the latter,depending upon the angularity of the friction-disks g This speedchanging and controlling mechanism is substantially the same as thatforming the subject-matter of United States Patent No. 529,713, grantedto me November 27, 1894, to which reference may be had.

An arm A on the side of the standard supports, as herein shown, acircular plate R, provided near its periphery with a series of holes R(see Fig. 3) of suitable size to receive the shanks of the drills orother tools of various sizes adapted to be used on the machine, and onits under side the plate R has a cam-rib R, which isengaged by afork Rat the end of a lever B, fulcrumed at R on an arm 9 extended from one ofthe bearings g, the inner end of the said arm R having thereon asegment-gear R in engagement with the adjacent gear 9 on the standard g.

By rotation of the tool support or carrier R the cam will act throughthe intervening mechanism to turn the friction disks or Wheels g andvary their angularity relative to the cooperating members M N, and thus"ary the speed of the former.

Inasmuch as the speed for drillsor similar tools is greater for those ofsmall diameter than for those of larger diameter I utilize theconnections between the carrier R and the speed changing mechanism justdescribed to automatically set the speed of, the machine to the diameterof the drill to be used.

An index P may be secured to the arm A and upturned adjacent theperiphery of the tool-support R, the shape of the cam B being such thatif the support or carrier R is turned until the drill of the proper sizeis opposite the index such movement will set the speedcontrollingmechanism to give the proper speed to the spindle for the tool of thatsize.

The shipper-shaft 0 (see Fig. 9) is longitudinally grooved at 0 to beentered by a .keyon a hub if, provided with a suitable handknob iandoppositely-extended arms 25 t in different horizontal planes, the hub25 having a spring-catch to engage one or the other of two notches t inthe bearing 0 of the shipper-shaft, the latter having another hearing 0on the traveler E. Stops Z 25 are adapted to be secured in the undercutgrooves 7 of the flange c on gear 0 to cooperate, respectively, with thearms 25' and 1 When the spindle has rotated sufficiently to bring thestop 25 into engagement with arm t, the shipper-shaft will be turned toreverse the direction of rotation of the main shaft, and thetool-spindle D will be rotated in the opposite direction until the otherstop 15 engages the arm t rocking the shipper-shaft in the oppositedirection and causing the direction of rotation of the spindle D to beagain reversed. This rotation of the tool-spindle first in one directionand then in the other is convenient for many purposes, and so far as Iam aware such arrangement is novel.

When it is not desired to utilize the automatic reversing device, thecatch 25 is released and the hub 15 moved down into the position shownin Fig. 9, so that the arm t t -will not be in the path of movement ofthe stops.

Myinvention is not restricted to the precise construction of partsasherein shown, as the same may be varied or rearranged without departingfrom the spirit and scope of my invention, and so far as I am aware itis broadly new to automatically vary the rate of speed of rotation of atool-spindle in accordance with the diameter of the tool to be used byor through the movement of the tool carrier or support.

Having fully described my invention, what I claim, and desire to secureby Letters Pat cut, is

1. In an apparatus of the class described, a tool-spindle, means,including speed-changin g mechanism, to rotate it at different speeds,and a controlling device for said mechanism, to automatically set thespeed of the spindle according to the diameter of the tool to be used,substantially as described.

2. In an apparatus of the class described, a tool-spindle, means torotate it, including speed-changing mechanism, and controlling meanstherefor including a movable tool-carrier and a fixed index, wherebywhen the carrier is moved to bring the tool to be used opposite theindex the speed-changing mechanism will thereby be automatically set toeffect rotation of the spindle at the proper speed for said tool,substantially as described.

3. In an apparatus of the class described, a tool spindle, means torotate it, including speed-changing mechanism, and a movabletool-carrier connected with and to control said mechanism, wherebymovement of the carrier will effect a proportional movement of the saidmechanism to rotate the spindle at the speed required for the diameterof the tool to be used, substantially as described.

4. In an apparatus of the class described, a tool-spindle, alarge and asmall gear connected therewith, a main shaft provided with two gearsadapted to be brought into engagement with the spindle-gears one at atime, manually-operated means to effect such engagement, andspeed-changin g mechanism for said shaft, including a driven pulleyloose relatively to the shaft, a pulley to be driven, connected torotate with the shaft, said pulleys being annularly concaved on theirinner faces, and a controlling friction-disk interposed be tween thesaid pulleys, substantially as described.

5. In an apparatus'of the class described, a rotatable tool-spindle, twoconcentric rigidlyconnected gears having a single, extended hub on whichthey are fixed, said hub being connected with and to permit longitudinalmovement of the spindle, a fixed bearing for the gear-hub, and means toregulate the longitudinal movement of the spindle, combined with a maindriving-shaft, two gears rotatable therewith and longitudinally movablethereon, and means to move said gears longitudinally, to bring one intoengagement with one of the spindle-gears, and disengage the other gears,and vice versa, substantially as described.

6. In an apparatus of the class described, a rotatable tool-spindle, alarge and a small gear rigidly connected together and connected to saidspindle to rotate it and also to permit longitudinal movement of thespindle, and a fixed bearing for said connected gears, combined with amain driving-shaft, two independent gears mounted upon and to rotatewith said shaft and separately movable longitudinally upon it, toseparately engage the small and large spindle-gears respectively, andmeans to disengage one driving-gear from its spindle-gear and to causeengagement of the other two gears,substantially as described.

7. In an apparatus of the class described, the main driving-shaft, twogears the hubs of which are connected to rotate with said shaft and bemovable longitudinally thereon,a camplate mounted in a fixed bearing, astud on one of said gear-hubs in engagement with the cam, a linkattached to the other hub and pivoted eccentrically on the cam, andmeans to rotate the latter, whereby the gears will be moved toward orfrom each other on the main shaft, substantially as described.

8. In an apparatus of the class described, a main standard, a platencarrier vertically movable thereon, means to clamp the carrier on thestandard, and a rotatable actuatinggear supported by the standard,combined with a threaded operating-shaft in engagement with the carrier,a gear on said shaft, and means to move said shaft longitudinally withthe carrier when unclamped, to engage or disengage the said gears,substantially as described.

9. In an apparatus of the class described, a main standard, aplatencarrier vertically movable thereon, means to clamp the carrier onthe standard, and a rotatable actuatinggear supported by the standard,combined with a rotatable shaft threaded to engage said carrier, avertically-movable bearing for said shaft, operable manually when thecarrier is unclainped, and a gear on the shaft, to be brought into meshwith the actuating-gear when the platen-carrier is to be raised orlowered by power, substantially as described.

10. In apparatus of the class described, a standard, a tool-spindle, amain shaft, means to vary the speed thereof, connections between saidshaft and spindle, to rotate the latter, and a platen-carrier-actuatinggear on the main shaft, combined with a platen-carrier, a lifting-shaftthreaded thereto and pro vided with a gear, and means to movesaidlifting-shaft to engage or disengage its gear and the actuating-gear,substantially as described.

11. In" an apparatus of the class described, a verticallongitudinally-movable tool-spindle, a fixed bearing, a hub rotatabletherein and splined to the spindle, a large and a small bevel-gear faston said hub, the former being on an annular flange provided withexternal grooves, and adjustable stops to beheld there in, combined witha main shaft, gears thereon to engage, one at a time, the small andlarge spindle-gears respectively, reversing mechanism for the mainshaft, and controlling means therefor operated by said stops,substantially as described.

12. In an apparatus of the class described, a rotatable tool-spi ndle,agear rotatable therewith and relatively to which the spindle islongitudinally movable, and adjustable stops movable with the gear,combined with a main driving-shaft having a gear to mesh with thespindle-gear,.and reversing mechanism controlled by said stops, torotate the tool-spindle first in one and then in the other direction,substantially as described.

1-3.. In an apparatus of the class described, a rotatable tool-spindle,a traveler, mechanism carried thereby to etfect feed of the spindlerapidly or slowly by hand, or mechanically, a driving-shaft to actuatesaid mechanism for mechanical feed of the spindle, and a singlecontrolling device to eifect either fast or slow feed by hand, or tocause engagement and disengagement of said driving-shaft and mechanism,substantially as described.

14. In an apparatus of the class described, a main driving-shaft,speedchanging mechanism therefor, including a driving-pulley and a pulley tobe driven, the latter fast on the shaft, said pulleys being aunularlyconcaved on their inner faces, an interposed frictiondisk, and a supporttherefor, combined with a movable tool-carrier, and connections betweenit and the disk-support,wherebymovement of the tool-carrier willproportionally vary the angula-rity of the friction-disk relatively tothe pulleys, to change the speed of the main shaft, substantially asdescribed.

15. In an apparatus of the class described, a rotatable tool-spindlehaving a feed-rack thereon, a traveler, gearing carried thereby toengage said rack and feed the spindle longitudinally, amanually-operated actuator for said gearing, independent means,including speed-changing mechanism, to actuate said gearing, and asingle controlling device to provide for manual or mechanical operationof the gearing, and to govern the speed of the former, substantially asdescribed.

16. In an apparatus of the class described, a longitudinally-movabletool-spindle, means to rotate it, reversing mechanism for said means,andcontrollingmeans for thereversin g mechanism,rotatable and concentricwith the spindle, whereby the latter will be automatically andpartiallyrotated first in one and then in the other direction,substantially as described.

17. A member adapted to be rotated, mechanism to rotate it in oppositedirections, and controlling means for said mechanism, governed directlyby and concentric with the rotatable member, whereby the latter will beautomatically and partially rotated first in one and then in the otherdirection, substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing Witnesses.

HENRY I-I. CUMMINGS.

Witnesses:

JOHN C. EDWARDS, AUGUSTA E. DEAN.

